Liquid–Liquid Interface Polar Engineering for Organic Piezoelectrics

Deformable optoelectronic devices are emerging as critical technologies for wearable healthcare systems and next-generation display and energy harvesting platforms. Their practical deployment, however, remains limited by accelerated degradation under ambient conditions. Penetration of water vapor and oxygen accelerates the failure of moisture-sensitive layers, making encapsulation a key determinant of operational lifetime. A fundamental trade-off exists between barrier performance and mechanical stretchability: organic materials offer high compliance but poor moisture resistance, whereas inorganic barriers provide excellent impermeability but suffer from brittleness. Addressing these competing requirements demands an integrated approach that considers material selection and fabrication methodology. This review highlights recent advances in stretchable encapsulation technologies, encompassing organic, inorganic, and hybrid materials, and outlines the core requirements for practical operation: high impermeability, mechanical compliance, and optical transparency. By correlating emerging experimental results with these criteria, this review establishes a framework for designing encapsulation strategies that reconcile mechanical and barrier demands.

The piezoelectric characteristics of transducer crystals may be expressed in terms of electromechanical coupling coefficient, mechanical compliance coefficient, and dielectric constant, all referring to the mode to be applied, and the density. The modes considered are face shear (utilized in the torque “Bimorph”), lateral expansion, thickness expansion, and thickness shear. Properties not readily expressed in circuit terms but of the highest practical importance are dielectric and mechanical strength and permissible temperature rise. Rochelle salt offers a coupling coefficient of 0.5 or more, combined with fairly high mechanical compliance and high dielectric constant for face shear and lateral expansion. Quartz combines a rather low coupling of about 0.1 with low electric compliance; these factors are disadvantageous for most transducer applications but may be outweighed by excellent stability. The newer crystals, ammonium dihydrogen phosphate (ADP) and lithium sulfate monohydrate (LH), combine fair stability against atmospheric conditions with intermediate dielectric constant and couplings about 0.3, the former for face shear and lateral expansion, the latter for thickness and volume expansion. Neutral potassium tartrate (DKT) in face shear or lateral expansion is indicated for transducer uses requiring fairly high coupling, up to 0.25, with a low temperature coefficient of resonant frequency. Polarized barium titanate ceramic takes its place besides the single crystals. It combines low mechanical compliance and very high dielectric constant with coupling of 0.20 for the lateral expansion and 0.45 for the thickness expansion. It may be shaped into curved transducer elements. A comparative table for these and some other substances will be given.

Methods: A retrospective analysis was conducted using linked pharmacy claims and cancer registry data from the population-based National Cancer Registry Ireland (NCRI). Women with stage IV breast cancer at initial diagnosis (2004-2006), who received HTx as 1st line treatment for ≥90 days were identified (tamoxifen, toremifene, fulvestrant, anastrozole, letrozole, exemestane). Compliance was calculated over the time that patients remained on HTx i.e. from the date of treatment initiation to the earliest of either HTx discontinuation or end of follow up (31/12/07, 3 years or death). Patients discontinuing HTx were assigned their compliance rate at this time for the remainder of follow-up. In the primary analysis Cox proportional hazard models with late entry at 90 days post HTx initiation and time varying compliance (defined dichotomously as: low < 80%, high ≥ 80%), were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for all-cause and breast cancer specific mortality. Secondary analyses of (a) time to treatment discontinuation and (b) compliance in the first 90 days of treatment were conducted. All models were adjusted for age, tumor grade, number/site of metastases, estrogen, progesterone and human epidermal growth factor 2 receptor status. Results: 359 women with stage IV breast cancer at diagnosis were identified. Of these, 151 received HTx as 1st line treatment. Median HTx compliance was 84.8%, (range 19.4%-100%; interquartile range 75.5%-100%). Demographic, tumor and treatment characteristics were similar between low (n=51) and high (n=100) compliance groups. The number and distribution of metastatic sites at diagnosis was also similar (low/high compliance: bone only 70.6%/70.0%, lung only 17.6%/18.0%, liver only 11.8%/14.0%, brain only 0.0%/0.0%, other 13.7%/17.0%, multiple sites 15.7%/18.0%). Compliance rates for both compliance groups increased marginally over time. Unadjusted all-cause mortality rates were 143 and 359 deaths/1000 woman years for low and high compliance respectively. Low compliance was associated with a 90% increased risk of all-cause (HR 1.90; 95%CI 1.06, 3.41) and breast cancer specific (HR 1.91; 95%CI 1.03, 3.55) mortality. In the secondary analyses low compliance was associated with a shorter time to HTx discontinuation (HR 1.97; 95%CI 1.01, 3.84). Low compliance within the first 90 days of treatment was associated with non-significantly increased mortality (all-cause HR 1.57; 95%CI 0.88, 2.80; breast cancer specific HR 1.58; 95%CI 0.85, 2.93). Discussion: This study demonstrates, for the first time to our knowledge, a significant association between low HTx compliance and increased mortality in patients with MBC. In addition, the observed association between compliance and treatment duration is consistent with a reduced time to disease progression in low compliance patients. The findings do not appear to be related to either the burden of metastatic disease at diagnosis or to increasing disease severity causing lower compliance over time. These results suggest that the development and evaluation of effective interventions to support HTx compliance in patients with MBC is warranted. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-08-12.

Many biological functions and dysfunctions rely on two fundamental processes, molecular assembly and the formation of condensed phases such as biomolecular condensates. Condensed phases generally form via phase separation, while molecular assemblies are clusters of molecules of various sizes, shapes, and functionality. We developed a theory that relies on thermodynamic principles to understand the interplay between molecular assembly and phase separation. We propose two prototypical classes of protein interactions and characterize their different equilibrium states and relaxation dynamics. We obtain results consistent with recent in vitro experimental observations of reconstituted proteins, including anomalous size distribution of assemblies, the gelation of condensed phases, and the change in condensate volume during ageing. Our theory provides the framework to unravel the mechanisms underlying physiological assemblies essential for cellular function and aberrant assemblies which are associated with several neurodegenerative disorders.

Organic materials hold considerable promise for thermoelectric applications, particularly in flexible devices, due to their pliable and lightweight nature. Recent progress in this domain has been fueled by enhancements in organic thermoelectric materials and more efficient device designs. This review offers a comprehensive overview of these advancements. It begins by detailing the evolution and performance optimization of high-efficiency organic thermoelectric materials, emphasizing both chemical and physical modifications. The review also delves into innovative design strategies for flexible devices, covering new structural approaches, performance modeling, and thermal management techniques. Moreover, it examines advanced manufacturing processes like 3D printing and thin-film deposition. To highlight global trends and challenges, the review integrates findings from top research institutions. The review projects future breakthroughs in material development, characterization techniques, and device optimization, particularly focusing on advances in materials such as PEDOT:PSS and PANI. It underscores strategies to boost conductivity and the Seebeck coefficient. Remarkably, innovative device designs have substantially enhanced energy conversion efficiency, while numerical simulations have improved output voltage and power density. Furthermore, cutting-edge manufacturing technologies like 3D printing and solution processing have facilitated the scalable production of intricate structures. In summary, these collective advancements drive high-performance, cost-effective, and sustainable thermoelectric technologies for diverse applications, including wearable electronics, energy harvesting, and thermal management.

Existing studies suggest a positive correlation between high compliance with enhanced recovery programs (ERP) and improved outcomes. While individual outcome measures have advantages, composite benchmarks, such as textbook outcome (TO), offer a more comprehensive assessment of healthcare performance. Given the link between ERP and postoperative outcomes, this study aims to investigate the impact of ERP on TO attainment after liver surgery (LS). A prospective multicenter cohort of patients undergoing LS and exposed to ERP from 2016 to 2022 in France was analyzed. The primary outcome was to compare the rates of TO achieved between patients with high ERP compliance (>70%) and those with low ERP compliance (<70%) after LS. A total of 706 patients were included in the study, and 217 (30.7%) achieved TO: 170 patients with high ERP compliance (24%) versus 47 patients (6.6%) with low ERP compliance attained TO (p<0.001). High ERP compliance was associated to an increased likelihood of achieving TO [odds ratio (OR)=1.49 (95% CI: 1.01, 2.24); p=0.049], while cholangiocarcinoma [OR=0.11 (95% CI: 0.02, 0.39); p=0.003], high complexity LS [OR=0.22 (95% CI: 0.13, 0.36); p<0.001], intraoperative hypotension requiring vasopressors [OR=0.29 (95% CI: 0.10, 0.68); p=0.010], and post-operative ileus [OR=0.08 (95% CI: 0.00, 0.37); p=0.013] were negatively associated to the likelihood of achieving TO. Patients with high ERP compliance after LS experience elevated rates of TO, compared to those with low ERP compliance.

To analyze the application effect of Adherence Rating Score (ARS) scale in the treatment of patients with tuberculosis. A total of 1 349 patients with tuberculosis from November of 2013 to May of 2014 in ten counties of Guizhou province were selected. Before treatment, ARS scale was applied. According to data related to the literature on compliance during the follow-up visits in late May and June (the patients were reviewed in late August), correlation of the evaluation score with the actual compliance was analyzed. There were 705 cases with high but 249 cases with low compliance when the ARS score was ≥4, while 213 cases with high compliance and 182 cases with low compliance when the ARS score was <4 in late May. The compliance of cases with ≥4 ARS score was significantly different from those cases with <4 ARS score in May (χ(2)=51.265,P<0.05). 637 cases with high compliance and 317 cases with low compliance when the ARS score was ≥4, and 193 cases with high compliance and 202 cases with low compliance when the ARS score was <4 in June (August), were discovered. The compliance of cases with ≥4 ARS score was significantly different from those cases with <4 ARS score in June ( χ(2)=37.865,P<0.05). Data from the comprehensive analysis, based on May and June (August), showed that there were 543 cases with high compliance and 411 cases with low compliance when the ARS score was ≥4, and 144 cases with high compliance and 251 cases with low compliance when the ARS score was <4 in late May. The compliance of cases with ≥4 ARS score was significantly different from those cases with <4 ARS score (χ(2)=46.802,P<0.05). RESULTS from the regression analysis showed that all of the late May, June (August) and continuous treatment periods were the factors influencing the compliance of the patients (OR=2.448, 95%CI: 1.910-3.138;OR=2.139, 95%CI: 1.678-2.726;OR=2.371, 95% CI: 1.853-3.034). The compliance based on score ARS scale and the actual investigation were significantly related and the compliance could be evaluated using the score ARS scale before the initiation of treatment and could be applied in Guizhou province.

Recent progress of organic and hybrid thermoelectric materials

Organic thermoelectric (TE) materials can directly convert heat to electricity, and they are emerging as new materials for energy harvesting and cooling technologies. The performance of TE materials mainly depends on the properties of materials, including the Seebeck coefficient, electrical conductivity, thermal conductivity, and thermal stability. Traditional TE materials are mostly based on low-bandgap inorganic compounds, such as bismuth chalcogenide, lead telluride, and tin selenide, while organic materials as promising TE materials are attracting more and more attention because of their intrinsic advantages, including cost-effectiveness, easy processing, low density, low thermal conductivity, and high flexibility. However, to meet the requirements of practical applications, the performance of organic TE materials needs much improvement. A variety of efforts have been made to enhance the performance of organic TE materials, including the modification of molecular structure, and chemical or electrochemical doping. In this review, we summarize recent progress in organic TE materials, and discuss the feasible strategies for enhancing the properties of organic TE materials for future energy-harvesting applications.

Enhanced recovery after surgery (ERAS) improves short-term outcomes after colorectal cancer (CRC) surgery, but its benefits on oncological results remain unclear. The objectives of this study are (1) to compare 5-year overall survival (OS) following non-metastatic CRC surgery between ERAS and conventional care (CC), and (2) to evaluate the association between ERAS compliance and OS. Patients undergoing curative resection for stage I-III CRC in a university hospital were reviewed. Utilizing the 2010-2012 CRC registry, 5-year OS of surgical patients between ERAS and CC were compared. Utilizing the 2010-2016 ERAS registry, 5-year OS between patients with high ERAS compliance (≥ 70%) and their counterparts were compared. Between 2010 and 2012, 349 patients had curative surgery: 70 (20%) with ERAS and 279 (80%) with CC. The 5-year OS was 80.3% in ERAS and 65.6% in CC (HR 0.54, 95%CI 0.33-0.88, p = 0.014). After adjustment with other variables, ERAS was associated with better 5-year OS for stage III CRC only (72.6% vs. 57.2%, adjusted HR 0.54, 95%CI 0.30-0.98, p = 0.041). Regarding ERAS compliance, 320 patients were reviewed: 232 (73%) with high compliance. The 5-year OS was 83.9% in high compliance and 69.6% in low compliance (HR 0.49, 95% CI 0.29-0.83, p = 0.007). After adjustment with cancer staging, high compliance had better 5-year OS in stage III CRC only (80.5% vs. 60.7%, adjusted HR 0.44, 95%CI 0.23-0.84, p = 0.013). ERAS was associated with improved 5-year OS following non-metastatic CRC surgery (especially stage III disease) than CC. High ERAS compliance had better OS than its counterpart.

To the Editor: Obesity has been recognized as an independent risk factor in other viral infections such as influenza A virus subtype H1N1 ((1)). Although data are scarce at this stage, there is also an unexplained increased prevalence of obesity in patients infected with SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) admitted to the intensive care units ((2)). In SARS-CoV-2 pneumonia, two different ventilatory phenotypes have been described ((3)). The L phenotype (Low) presents with low elastance and high compliance, low ventilation/perfusion ratio, and decreased recruitability; in this case, the factor limiting pulmonary function will be perfusion. Moreover, the H phenotype (High) presents with high elastance and low compliance, pulmonary shunts, and high recruitability; the factor limiting pulmonary function will be ventilation ((3)). In our intensive care unit, we have observed an unexplained increased prevalence of patients with obesity and SARS-CoV-2 pneumonia with ventilatory phenotype H (acute respiratory distress syndrome–like). From the ventilatory point of view, the patients need high positive end-expiratory pressure and respond well to recruitment maneuvers. The incidence of acute respiratory distress syndrome is increased in patients with obesity ((4)). To date, there are no studies that mention the association between the ventilatory phenotypes of COVID-19 and obesity. We suggest that understanding these relationships is crucial and clinically important in the treatment of patients with obesity and COVID-19 pulmonary complications. We urge authors to report ventilatory phenotypes in their studies of patients with obesity and pulmonary complications of COVID-19. The authors declared no conflict of interest.

Organic solar cells (OSCs), exhibiting better sensitivity to different light intensities and higher power conversion efficiencies (PCEs) under indoor illumination, have great potential to be simultaneously used for solar energy harvesting and optical communication. However, the poor intrinsic molecular stacking and phase separation in active layers significantly hinder the charge transport and extraction in OSCs for achieving this aim. Here, an effective heterohalogen‐substitution asymmetric additive strategy is proposed to fine‐tune the non‐covalent interaction with nonfullerene molecules and optimize the morphology of active layer, which greatly boosts both the OSC photovoltaic performance with the PCEs of up to 18.30% and 29.52% under AM 1.5G and indoor light illumination respectively, and the ‒3 dB communication bandwidths of 4.11, 3.14, and 3.04 MHz at red, green, and blue (RGB) wavelengths respectively. Of particular note, combining the wavelength division multiplexing and adaptive bit‐loading technologies, the visible light communication system comprised of the RGB light sources and additive‐treated OSCs delivers more remarkable data throughput of 302.7 Mb s−1 and higher harvesting power of 7.38 mW simultaneously, presenting an excellent self‐powered capability for enhanced endurance. This work demonstrates that high‐performance OSCs with excellent energy harvesting and wireless communication capacity can be perfectly achieved by a heterohalogen‐substitution asymmetric additive strategy.

Piezoelectric polymer nanofibers are promising for wearable electronics due to their mechanical compliance and electromechanical responsiveness. Poly(vinylidene fluoride)‐trifluoroethylene (PVDF‐TrFE) is widely used for its ferroelectric β ‐phase and favorable piezoelectric properties, yet its limited elasticity hinders applications in soft bioelectronics. Electrospun PVDF‐TrFE mats can stretch through fiber rearrangement but lack true elastic recovery unless molecular interactions and junctions are modified. Achieving nanofiber networks that are both stretchable and piezoelectrically stable under cyclic strain remains a challenge. Here, we report a strategy combining PVDF‐TrFE with a small fraction of poly(ethylene glycol) bis(amine) (PEG‐diamine) and thermal annealing to form fused nanofibrous mats with enhanced elasticity and stable piezoelectric output. The blended mats doubled the strain‐to‐failure (~30%) compared to pure PVDF‐TrFE (~14%) and showed Mullins‐like elastic recovery up to approximately 9% with reduced hysteresis. Piezoelectric response improved by approximately 25% in peak voltage (~150 mV), with greater signal stability. Structural analyses (Fourier‐transform infrared [FTIR], differential scanning calorimetry [DSC], and X‐ray diffraction [XRD]) confirmed increased β ‐phase content and selective cross‐linking in amorphous domains without compromising ferroelectric order. This work demonstrates a scalable material‐based approach to improve elasticity and durability in electrospun piezoelectric fibers, enabling stretchable and skin‐conformable sensors for smart fabrics, wearable health monitors, and energy harvesting.

The growing demand for sustainable and distributed energy solutions has driven increasing interest in triboelectric nanogenerators (TENGs) as platforms for energy harvesting and self-powered sensing. Biowaste-based triboelectric nanogenerators (BW-TENGs) represent an attractive strategy by coupling renewable energy generation with waste valorization under the principles of the circular bioeconomy. This review provides a comprehensive overview of BW-TENGs, encompassing fundamental triboelectric mechanisms, material categories, processing and surface-engineering strategies, device architectures, and performance evaluation metrics. A broad spectrum of biowaste resources-including agricultural residues, food and marine waste, medical plastics, pharmaceutical waste, and plant biomass-is critically assessed in terms of physicochemical properties, triboelectric behavior, biodegradability, biocompatibility, and scalability. Recent advances demonstrate that BW-TENGs can achieve electrical outputs comparable to conventional synthetic polymer TENGs while offering additional advantages such as environmental sustainability, mechanical compliance, and multifunctionality. Key application areas, including environmental monitoring, smart agriculture, wearable and implantable bioelectronics, IoT networks, and waste management systems, are highlighted. The review also discusses major challenges limiting large-scale deployment, such as material heterogeneity, environmental stability, durability, and lack of standardization, and outlines emerging solutions involving material engineering, hybrid energy-harvesting architectures, artificial intelligence-assisted optimization, and life cycle assessment frameworks.

Textile electronics are poised to revolutionize future wearable applications due to their wearing comfort and programmable nature. Many promising thermoelectric wearables have been extensively investigated for green energy harvesting and pervasive sensors connectivity. However, the practical applications of the TE textile are still hindered by the current laborious p/n junctions assembly of limited scale and mechanical compliance. Here we develop a gelation extrusion strategy that demonstrates the viability of digitalized manufacturing of continuous p/n TE fibers at high scalability and process efficiency. With such alternating p/n-type TE fibers, multifunctional textiles are successfully woven to realize energy harvesting on curved surface, multi-pixel touch panel for writing and communication. Moreover, modularized TE garments are worn on a robotic arm to fulfill diverse active and localized tasks. Such scalable TE fiber fabrication not only brings new inspiration for flexible devices, but also sets the stage for a wide implementation of multifunctional textile-electronics.